1. Field
The present invention relates to the art of lifting a coil from a stack of coils and transporting it without relying upon manual lifting of the coil.
2. Description of the Prior Art
Many elongate materials such as steel strip, aluminum strip and other metals are wound into the form of a coil having a central hollow core. Such coils may often weigh from 100-1200 lbs., or more. After the coils are manufactured by the rolling mill, they are typically stored in stacked fashion with one coil laid upon the other, and superimposed with their central cores substantially aligned with each other. A stack of coils can be transported to the user on a pallet or other suitable transport platform. The user is then confronted with the problem of lifting one coil at a time off the stack so that he can transport it to a suitable holder or other device for feeding the coil into a machine in which the strip is to be processed.
The typical prior art methods for lifting a coil from a stack of coils are in some respects primitive or dangerouos, but in any event not particularly satisfactory. It is common for a workman to manually lift a coil from its flat horizontal or stacked position to a vertical position in order to lift it onto the forks of a fork lift truck. If the coil is heavy, two men may be necessary for this work. There is great danger of crushed fingers or toes if a coil should slip during such manual handling, but the method is practiced on a surprisingly large scale in many factories. Another solution is to stack the coils with wedges or spacers between adjacent coils so that the forks of a fork lift truck can be driven into the space between coils in order to lift the uppermost coil. However, this in unsatisfactory because of the problems of coils slipping from the stack due to their separated fashion, either in transport or in storage, so that this method has not enjoyed particularly wide use. Other prior art methods may utilize attaching a handle or other tool to a coil to attempt to facilitate the problem of lifting a coil onto a fork lift truck.
The general unsuitability of the prior art methods heretofore practiced have resulted in the removal of a coil of strip steel, for example, from a stack of coils being a dangerous and time consuming operation because of the great amount of manual labor involved in it. The present invention in both its method and apparatus aspects seeks to abate these problems.